This invention relates to an information reproducing system, an information recording/reproducing system, and a recording medium applicable to the system, and more particularly to a reproducible playback DVD player, a recording/playback DVD player, and an optical disk applicable to these DVD players.
In recent years, a system for playing back an optical disk on which images (moving pictures), sound, and others have been recorded has been developed. LDs (laser disks) or video CDs (video compact discs) which enable the playback of movie software, karaoke, and the like have been put on the market and widely used.
The DVD standard using the internationally standardized MPEG-2 (Moving Image coding Experts Group) scheme as a moving-picture compression scheme and the AC-3 audio compression scheme as an audio coding mode has been proposed. Optical disks complying with the standard (hereinafter, just referred to as DVD disks) are commercially available and widely used.
The DVD standard adopts a moving-picture compression scheme conforming to the MPEG-2 system layers, supports AC-3 audio or MPEG audio as an audio coding mode, and has a data structure including not only a sub-picture pack in which sub-picture data obtained by run-length compressing the bit map data for subtitles has been stored independently but also a navigation pack in which special playback control data, such as fast-forward playback or fast-rewind playback data, has been stored independently in a similar manner. Furthermore, the DVD standard supports ISO 9660 and micro UDF to allow computers to read data.
Presently, the DVD standard has been determined in the form of playback-only formats and therefore is not applicable to home recording/reproducing optical disks and their players. Thus, when recording/reproducing systems for home use are constructed according to the DVD standard, it is clear that the following problems arise. A playback-only DVD video player generally has a resume playback function of, after the interruption of playback, resuming the playback where it was interrupted. Specifically, in the resume playback function, when the playback of the inserted disk has been interrupted, information on the location (address) of the place where playback was just in progress is stored in the RAM in the player, information on the location is accessed, for example, the resume playback key is pressed, or the play key is pressed once to read data on the location where playback was just in progress from the memory, and thereafter, the playback is resumed where it was interrupted, or the play key is pressed again to restart the normal playback.
In the resume playback function in a presently popularized playback-only DVD video player, when the disk is removed, the playback end information on the disk disappears. Even if the same disk is inserted again, it is impossible to resume playback where the playback of the disk was interrupted. This causes a problem: the user himself or herself has to seek the location to be played back. A playback-only DVD video player of the latest model uses an EE-ROM as a memory for storing the playback end information and has the information disk by disk (for example, being capable of storing the playback end information for up to ten disks). Even when the disk is changed, the location to be played back can be searched for.
However, there is a limit to the storage capacity of the memory that uses the method of storing the playback end information. Thus, it is expected that unlimited replacement of disks will make it impossible to search for the playback location.
The DVD player systems have the following problem: when the disk is removed, the playback end information on the disk disappears, and therefore, the user has to seek the playback location, even when the same disk is inserted, to resume playback where it was interrupted.
An object of the present invention is to provide a disk which enables the interruption of playback where it was interrupted, provided that, after the disk was removed from a playback system capable of recording, the disk is installed again in the system.
Another object of the present invention is to provide an information reproducing system capable of resuming playback where it was interrupted, provided that, after a disk was removed from a system capable of recording, the disk is installed again in the system.
Still another object of the present invention is to provide an information recording/reproducing system capable of resuming playback where it was interrupted, provided that, after a disk was removed from a playback system capable of recording, the disk is installed again in the system.
The foregoing objects are accomplished by providing an information recording medium on which video information, audio information, and others can be recorded, the information recording medium characterized by including an area in which playback interrupt information for resuming playback during the interruption of playback can be recorded.
According to the invention, there is provided an information recording/reproducing system for reproducing video information and audio Information from an information recording medium on which video information, audio information, and others can be recorded and which includes a recording area in which playback interrupt information for resuming playback during the interruption of playback can be recorded, the information reproducing system characterized by comprising a specifying section for specifying the resumption of playback and a playback interrupt reading section for reading the playback interrupt information from the recording area according to the specification from the specifying section and in that the system resumes playback where playback was interrupted, according to the specification from the specifying section.
Furthermore, according to the invention, there is provided an information recording/reproducing system for reproducing video information and audio information from an information recording medium on which video information, audio information, and others can be recorded and which includes a recording area in which playback interrupt information for resuming playback during the interruption of playback can be recorded, the information recording/reproducing system characterized by comprising a specifying section for specifying the interruption of playback and a recording section for recording the playback interrupt information in the recording area according to the specification from the specifying means.
With the information recording/reproducing system of the present invention, since the playback interrupt information has been written on the disk, even when the disk is removed from the system, reinstalling the disk into the system makes it possible to resume playback.